LVO and 90m visual from cockpit A320 question.
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Pleasure, be assured my aggravation was not pointed at you. When I read the Co. manual for the first time, I couldn't make any sense of it. Reviewing it after an explanation was somewhat more successful.
The first part's RVR may only be replaced by an assessment for LVTO 400-150 m. The 90 m segment is a required characteristic for 150-125 m, and no replacing or substitution is allowed. Such has been the case for long decades, irrespective of the fact that many very large airlines have been teaching their pilots the nonsense of counting lights for ages.
The first part's RVR may only be replaced by an assessment for LVTO 400-150 m. The 90 m segment is a required characteristic for 150-125 m, and no replacing or substitution is allowed. Such has been the case for long decades, irrespective of the fact that many very large airlines have been teaching their pilots the nonsense of counting lights for ages.
The single `*` at the head of the table in the RVR column (The reported RVR value representative of the initial part of the take-off run can be replaced by pilot assessment) could be interpreted as applying to all the cases given, including the 125m scenario?
Can you confirm then that it is not permitted (in a scenario where the RVR is, for example, 100/125/125) to line up and establish whether you can see, say, 8 or 9 RW centreline lights ahead of you thereby confirming that in `real terms` the RVR at the TDZ is indeed 125 m?
I am happy that you can`t line up and say: well I can see a 90m visual segment (6 lights) ahead so let`s go for it!
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Off the top of my head I was under the impression that all RVRs had to be above 125m AND the pilots could see a visual segment of at least 6 lights. (and of course we always can!)
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The single `*` at the head of the table in the RVR column (The reported RVR value representative of the initial part of the take-off run can be replaced by pilot assessment) could be interpreted as applying to all the cases given, including the 125m scenario?
The argument I prefer goes as follows: The logic is the RVR measuring device is not located on the runway, it is probably 50m to the side over the grass. Thus there could be a discrepancy between what is being measured / reported, and what the pilot can actually see from the flight deck. Therefore before we start the take off, we are allowed to asses the initial part of the take off run ourselves (by counting the lights) and may replace the touch down reported value.
There was a typo several years ago which seemed to exclude RVR 125m - but that has now been corrected.
https://www.easa.europa.eu/sites/def...20Part-SPA.pdf
Only half a speed-brake
Oh what a mess, let's see:
EU-OPS Appendix 1 (New) to OPS 1.430 - the regulation preceding the current EASA IR.
These are the basic rules for TKOF down to 150 m, and the table does not show any lower values. On the next page, the specific case for less than 150 m is discussed:
The Exceptions to sub-paragraph (3)(a)(i) - the first picture - are clearly not derogations but rather additional restrictions imposed on top of the original, down-to-150-m, requirements. Thus where (3)(a)(i) explicitly says the first RVR if not achieved can be replaced, Paragraph 4(E) removes that possibility.
Was it a typo, or the actual intention of the law-maker instead?
EU-OPS Appendix 1 (New) to OPS 1.430 - the regulation preceding the current EASA IR.
These are the basic rules for TKOF down to 150 m, and the table does not show any lower values. On the next page, the specific case for less than 150 m is discussed:
The Exceptions to sub-paragraph (3)(a)(i) - the first picture - are clearly not derogations but rather additional restrictions imposed on top of the original, down-to-150-m, requirements. Thus where (3)(a)(i) explicitly says the first RVR if not achieved can be replaced, Paragraph 4(E) removes that possibility.
Was it a typo, or the actual intention of the law-maker instead?
The required RVR value must be achieved for all of the relevant RVR reporting points with the exception given in Note 3 above.
vs.
(when) The required RVR value has been achieved for all of the relevant RVR reporting points.
vs.
(when) The required RVR value has been achieved for all of the relevant RVR reporting points.
Only half a speed-brake
I tried to search a bit deeper.
Find 1: The text above is identical since JAA OPS, 1999ish.
Find 2: The ICAO Doc 9365 Manual of All Weather Operations shows Table 6-2, which is inconclusive to this discussion. The order of possible priority between notes 1 and 4 cannot be determined. I still like to note that while ICAO has a single table with values all the way down to 75 m, the ECAC/JAA people chose to split it and define the (overlapping) notes more precisely, when publishing the EU regulation.
Find 3: I couldn't find the FAA version of this.
Find 4: The Australian CAAP LVO-1 https://www.casa.gov.au/sites/g/file.../ops/lvo-1.pdf clearly prohibits the self-replacement of RVR below 350 metres.
Since there WAS a re-design of the relevant paragraph, the key question is: did EASA have a change of heart? Was there a NPA process to allow 75/125/125 departures based on "seeing lights"...?
Find 1: The text above is identical since JAA OPS, 1999ish.
Find 2: The ICAO Doc 9365 Manual of All Weather Operations shows Table 6-2, which is inconclusive to this discussion. The order of possible priority between notes 1 and 4 cannot be determined. I still like to note that while ICAO has a single table with values all the way down to 75 m, the ECAC/JAA people chose to split it and define the (overlapping) notes more precisely, when publishing the EU regulation.
Find 3: I couldn't find the FAA version of this.
Find 4: The Australian CAAP LVO-1 https://www.casa.gov.au/sites/g/file.../ops/lvo-1.pdf clearly prohibits the self-replacement of RVR below 350 metres.
Since there WAS a re-design of the relevant paragraph, the key question is: did EASA have a change of heart? Was there a NPA process to allow 75/125/125 departures based on "seeing lights"...?
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I tried to search a bit deeper.
Find 1: The text above is identical since JAA OPS, 1999ish.
Find 2: The ICAO Doc 9365 Manual of All Weather Operations shows Table 6-2, which is inconclusive to this discussion. The order of possible priority between notes 1 and 4 cannot be determined. I still like to note that while ICAO has a single table with values all the way down to 75 m, the ECAC/JAA people chose to split it and define the (overlapping) notes more precisely, when publishing the EU regulation.
Find 3: I couldn't find the FAA version of this.
Find 4: The Australian CAAP LVO-1 https://www.casa.gov.au/sites/g/file.../ops/lvo-1.pdf clearly prohibits the self-replacement of RVR below 350 metres.
Since there WAS a re-design of the relevant paragraph, the key question is: did EASA have a change of heart? Was there a NPA process to allow 75/125/125 departures based on "seeing lights"...?
Find 1: The text above is identical since JAA OPS, 1999ish.
Find 2: The ICAO Doc 9365 Manual of All Weather Operations shows Table 6-2, which is inconclusive to this discussion. The order of possible priority between notes 1 and 4 cannot be determined. I still like to note that while ICAO has a single table with values all the way down to 75 m, the ECAC/JAA people chose to split it and define the (overlapping) notes more precisely, when publishing the EU regulation.
Find 3: I couldn't find the FAA version of this.
Find 4: The Australian CAAP LVO-1 https://www.casa.gov.au/sites/g/file.../ops/lvo-1.pdf clearly prohibits the self-replacement of RVR below 350 metres.
Since there WAS a re-design of the relevant paragraph, the key question is: did EASA have a change of heart? Was there a NPA process to allow 75/125/125 departures based on "seeing lights"...?
But EU Ops rules are clear. As pointed out several times in this discussion.
6 lights and off I go.
Only half a speed-brake
Clear they are, in EU-OPS which no longer is the applicable regulation. Somewhat more cloudy in EASA-IR, for those who insist on what favours them. Clear enough if you dare to think before taking conclusions.
There is one thing laid out in the ICAO doc, and believe it or mot the rules worldwide are quite harninized. The Oz rulebook is a demonstration how the same thing could be written in a different format.
Nothing has changed for decades. Why would there be the requirement to have any TDZ RVR if it can be always replaced?
There is one thing laid out in the ICAO doc, and believe it or mot the rules worldwide are quite harninized. The Oz rulebook is a demonstration how the same thing could be written in a different format.
Nothing has changed for decades. Why would there be the requirement to have any TDZ RVR if it can be always replaced?
Only half a speed-brake
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Nothing has changed for decades.
"Take -off Ban .... Note: Pilot assessment of TDZ RVR when practical always overrides the reported RVR or met visibility. Pilot assessment may not be practical where runways are humped or the RVR limit is high"
Why would there be the requirement to have any TDZ RVR if it can be always replaced?
Reading my company manuals with a fine tooth comb as flight detent suggested a note for 150m and below says RVR required for all relevant RVR’s. I can see how this supersedes and overrules the other note about using pilot assessment.
In over 10years only once have a ever seen a TDZ RVR below 125m and that was in MXP. It was a 100m and there certainly wasn’t any hint or requests from any departing aircraft to trot off down to the numbers and count the lights on the centre line in order to depart below the reported RVR.
Always a a little cautious regarding RVR’s as I do know someone ( although a slightly different situation to this) who got fined a couple of grand for landing below RVR minima. So not just a telling off from the company but a potential hit in the wallet!
My early sims remember a lot of counting of centreline lights but have to admit doesn’t seem to occur as much recently. Although saying that I recently listened to a well regarded podcast on Airbus 320 lvo and they were talking about counting 6lights
All the best
mooneyboy
In over 10years only once have a ever seen a TDZ RVR below 125m and that was in MXP. It was a 100m and there certainly wasn’t any hint or requests from any departing aircraft to trot off down to the numbers and count the lights on the centre line in order to depart below the reported RVR.
Always a a little cautious regarding RVR’s as I do know someone ( although a slightly different situation to this) who got fined a couple of grand for landing below RVR minima. So not just a telling off from the company but a potential hit in the wallet!
My early sims remember a lot of counting of centreline lights but have to admit doesn’t seem to occur as much recently. Although saying that I recently listened to a well regarded podcast on Airbus 320 lvo and they were talking about counting 6lights
All the best
mooneyboy
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For last 20 years every checkride I have had I have heard different ideas and views from various instructors .... And this forum really drives home the fact that these regulations are so poorly written that nobody understands or can agree on something that should be very clear!
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these regulations are so poorly written that nobody understands or can agree on something that should be very clear!
Does anybody have a more recent document than May 16?
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Yes I’m in EASA land ( well until 29th Mar but that’s a different topic).
Ive heard of the situation of cat3b let’s say AMS 18R you could use 1 RVR on 27 as it’s same Aerodrome.
Thanks I think I now understand the 90m segment.
My ops manual says ‘The touchdown RVR is always controlling for all instrument approaches’. However and this maybe the change that came in a couple years ago it then says ‘If reported and relevant, the mid point and and stop end are also controlling’.
Does this imply if the TDZ rvr is not working then the mid point is now relevant and controlling? So if not using rollout you would need the 125m mid point as this is now controlling. Is this the right logic?
Ive heard of the situation of cat3b let’s say AMS 18R you could use 1 RVR on 27 as it’s same Aerodrome.
Thanks I think I now understand the 90m segment.
My ops manual says ‘The touchdown RVR is always controlling for all instrument approaches’. However and this maybe the change that came in a couple years ago it then says ‘If reported and relevant, the mid point and and stop end are also controlling’.
Does this imply if the TDZ rvr is not working then the mid point is now relevant and controlling? So if not using rollout you would need the 125m mid point as this is now controlling. Is this the right logic?
Good questions, this is what the forums should be about
Recently asked one of my companies examiners and he also reiterated not using pilot assessment below 150m RVR.
Yes as you mention above imagining a court scenario and you having to defend your position can help you come to a sensible decision.
Thanks everyone for help, tips and advice.
Mooneyboy
Mooneyboy
Yes as you mention above imagining a court scenario and you having to defend your position can help you come to a sensible decision.
Thanks everyone for help, tips and advice.
Mooneyboy
Mooneyboy
